Can Place Flowers - LeetCode

https://leetcode.com/problems/can-place-flowers/?envType=study-plan-v2&envId=leetcode-75

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You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent plots.

Given an integer array flowerbed containing 0’s and 1’s, where 0 means empty and 1 means not empty, and an integer n, return true if n new flowers can be planted in the flowerbed without violating the no-adjacent-flowers rule and false otherwise.

Example 1:

Input: flowerbed = [1,0,0,0,1], n = 1
Output: true

Example 2:

Input: flowerbed = [1,0,0,0,1], n = 2
Output: false

Constraints:

  • 1 <= flowerbed.length <= 2 * 104
  • flowerbed[i] is 0 or 1.
  • There are no two adjacent flowers in flowerbed.
  • 0 <= n <= flowerbed.length
class Solution:
    def canPlaceFlowers(self, flowerbed: List[int], n: int) -> bool:
        count = 0
        flowerbed = [0] + flowerbed + [0]

        for i in range(1, len(flowerbed) - 1):
            if flowerbed[i-1] == 0 and flowerbed[i+1] == 0 and flowerbed[i] == 0:
                flowerbed[i] = 1
                count += 1
        return count >= n

解决问题的思维上，应该更多的考虑全面，不执着于人的思维。

class Solution {
    public boolean canPlaceFlowers(int[] flowerbed, int n) {
        int count = 0;
        for (int i = 0; i < flowerbed.length; i++) {
            if ((i == 0 || flowerbed[i-1] == 0) && (i == flowerbed.length - 1 || flowerbed[i+1] == 0) && flowerbed[i] ==0 ){
                flowerbed[i] = 1;
                count += 1;
            }
        }
        return count >= n;
    }
}

class Solution {
public:
    bool canPlaceFlowers(vector<int>& flowerbed, int n) {
        int count = 0;
        flowerbed.insert(flowerbed.begin(), 0);
        flowerbed.push_back(0);

        for (int i = 1; i < flowerbed.size()-1; ++i) {
            if (flowerbed[i-1] == 0 && flowerbed[i] == 0 && flowerbed[i+1] == 0){
                flowerbed[i] = 1;
                count += 1;
                if (count >= n){
                    return true;
                }
            }
        }
        return count >= n;        
    }
};